How long can a tourniquet be left in place? We want to get that tourniquet off as quickly and as safely as possible. And our goal really is to do that in less than two hours. Studies show that in less than two hours, there's a very low chance of any permanent damage being done. So in general, if that tourniquet's been on longer than six hours, we do not want to take that tourniquet off in the pre-hospital environment.

And that's because you have ongoing ischemia once you apply that tourniquet to the rest of the limb. And that can create complications once you start perfusing that limb again, so you need to manage those complications in an ICU-type setting. If it's a massive injury, if there's an amputation, we're not even going to think about removing that tourniquet.

For more information on this, check out deployedmedicine.com as a great resource for tourniquet application, tourniquet times, and guidelines from the Committee on Tactical Combat Casualty Care.